1. Field of the Invention
The present disclosure relates to a backlight module, and more particularly, to a backlight module comprising a light guide pipe for guiding lights together with an optical substrate for reflecting the lights.
2. Description of the Prior Art
Currently, photo-electric display technologies, following the semiconductor industries, have become a new integrated technology invested by many countries, and have been generally recognized as the most potential integrated technology industry by the academia and industry. Technology leading countries, such as U.S.A, Japan, Europe, have successively entered this technical field and are actively involved in research and design of this field. The applications of the photo-electric display technologies are very wide, such as image display applications, information storage applications, and optical communications applications. Therefore, the competitiveness of Taiwan can be improved by developments of the photo-electric display technologies.
In various kinds of backlight module technologies, the US patent with U.S. Pat. No. 6,655,825 has disclosed a technology of mixing colors and guiding lights by using coupling fibers and blending fibers. However, the lights transferred from the light source to the light guiding plate of the display have passed several times of couplings, and thus the utilization efficiency of the light source cannot be easily enhanced.
In the US patent with U.S. Pat. No. 6,714,185, a method for controlling the emergence angle of the lights by disposing different diffusion lines on a fiber having its head and tail connected to the same light source in order to form three-dimensional images is disclosed. However, by adopting the backlight module disclosed in this patent, the panel space utilization efficiency is too poor, and the coupling efficiency of the light source is much worse than the conventional technologies.
In the US patent with U.S. Pat. No. 5,461,548, a panel with a light pipe is disclosed, which utilizes a transparent PVC pipe to hitch the cores of several optical fibers into a beam of light pipe, and then the lights are transferred and emitted to the panel through the arrangements of the light pipes. However, in such a way, optical interference between different optical fibers may lower the efficiency. In addition, its manufacturing process is too difficult for mass production.
In the US patent with U.S. Pat. No. 5,568,964, a flexible optical fiber panel is disclosed, which couples the lights, emitted from at least one lighting layer packaged along the side edges and/or terminal edges, to the weaved optical fibers and uniformly emits the lights on the panel. However, in such a way, the manufacturing difficulty and cost will be increased. In addition, by adopting the superposition method to increase the amount of light emission, its efficiency will be sharply reduced.
In the TWN Patent with Patent No. 534970, a high-intensity fiber color backlight module is disclosed, which uses R, G, B colors as light sources to be coupled to specific fibers, and then the lights are emitted from the optical shutters of the fiber through geometric structures of the fibers. However, this method still cannot avoid the problem of light interfere.
As abovementioned, a light guide plate is needed in the backlight modules of conventional flat panel displays for uniformly transferring lights. However, when the size of the flat panel displays getting larger, the thickness of the light guide plate will be accordingly increased, which may results in facing the challenges of the volume of large-scale backlight modules being too large and complicated manufacturing processes. In addition, the fiber backlight module has a high cost, a large volume, and high energy loss. Hence, how to provide a backlight module with a low cost, a simple manufacturing process, and a high luminous efficiency has become an important topic in this field.